Study of heavy-flavor quarks produced in association with top-quark pairs at s √ =7 TeV using the ATLAS detector

Using a sample of dilepton top-quark pair (tt ¯ ) candidate events, a study is performed of the production of top-quark pairs together with heavy-flavor (HF) quarks, the sum of tt ¯ +b+X and tt ¯ +c+X , collectively referred to as tt ¯  + HF . The data set used corresponds to an integrated luminosity of 4.7  fb −1 of proton-proton collisions at a center-of-mass energy of 7 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. The presence of additional HF (b or c ) quarks in the tt ¯ sample is inferred by looking for events with at least three b -tagged jets, where two are attributed to the b quarks from the tt ¯ decays and the third to additional HF production. The dominant background to tt ¯  + HF in this sample is tt ¯ +jet events in which a light-flavor jet is misidentified as a heavy-flavor jet. To determine the heavy- and light-flavor content of the additional b -tagged jets, a fit to the vertex mass distribution of b -tagged jets in the sample is performed. The result of the fit shows that 79 ± 14 (stat) ± 22 (syst) of the 105 selected extra b -tagged jets originate from HF quarks, 3 standard deviations away from the hypothesis of zero tt ¯  + HF production. The result for extra HF production is quoted as a ratio (R HF ) of the cross section for tt ¯  + HF production to the cross section for tt ¯ production with at least one additional jet. Both cross sections are measured in a fiducial kinematic region within the ATLAS acceptance. R HF is measured to be [6.2±1.1(stat)±1.8(syst)]% for jets with p T >25  GeV and |η|<2.5 , in agreement with the expectations from Monte Carlo generators.

TTIP and Public Procurement: Going beyond the tip of the iceberg. CEPS Policy Brief No. 339, March 2016

Trade negotiations involving international public procurement rules are on the rise, stimulating a growing interest in having a clear picture of the economic stakes involved, including the current level of international openness. A recent paper published by the European Centre for International Political Economy (Messerlin, 2016) made an attempt to provide a range of estimates for the EU and the US and found relatively low rates of import penetration. This analytical approach, however, looked only at the ‘tip of the procurement iceberg’, as the data used covered primarily only one modality of international procurement (direct cross-border), which is not the main avenue for international government procurement. Other modalities, such as procurement from foreign subsidiaries established in Europe, account for much more. Such an approach therefore ignores the main modalities through which foreign firms win EU contracts. Once these other main procurement modalities are taken into account, EU openness in procurement is much higher. Comparable data across all modalities do not yet exist for the US, but we do have clear evidence that the US has introduced the largest number of protectionist procurement measures since 2008 affecting all modalities for international procurement. Against this background, this Policy Brief makes four basic points: i. Public procurement is a key area of trade negotiations, and TTIP is no exception to this rule. ii. The existing levels of openness in procurement markets need to be assessed across all three main procurement modalities and not based only on direct cross-border procurement, which is not the main procurement avenue. According to this comprehensive metric, the EU market already has a high foreign participation rate, including by US companies. iii. Unfortunately, similar data do not exist for the US market. But there is growing evidence of discriminatory measures introduced in recent years, which impede the ability of EU firms to compete on a level-playing field in US procurement markets. iv. The importance of procurement as a key negotiating area requires better data and a greater analytical engagement.

American ornithology : or, The natural history of the birds of the United States /

The plates drawn chiefly by Wilson, with the assistance of Peale, Audubon, and Rider.

Lucian the dreamer /

Mode of access: Internet.

American ornithology; or, the natural history of the birds of the United States.

Mode of access: Internet.

The thought of God in hymns and poems /

Includes an index of first lines: p. [133]-135.

The Colonial records of the state of Georgia /

Includes indexes.

The story of the Fifty-Fifth Regiment Illinois Volunteer Infantry in the Civil War, 1861-1865 /

pt.1. From Chicago in Arkansas post, October, 1861 to January, 1863 / by Lucian B. Crooker -- pt.2. From Young's Point to Atlanta, January, 1863 to November, 1864 -- pt.3. From Atlanta to Chicago, November, 1864 to August, 1865 / by John G. Brown.

A new systematic arrangement of vertebrated animals /

Text in Latin.

Library of Southern literature,

Vol. 17 (Suppl. no. 1) edited by E. A. Alderman and C. A. Smith.

A standard history of Georgia and Georgians,

Vols. IV-VI, biographical.

Library of southern literature;

Vol. 14 edited by C. A. Smith; v.15-16, by L. L. Knight.

The complete cost-keeper: some original systems of shop cost-keeping or factory accounting, together with an exposition of the advantages of account keeping by means of cards instead of books, and a description of various mechanical aids to factory accounting,

Mode of access: Internet.

Method of analysis and quality-assurance practices for determination of pesticides in water by solid-phase extraction and capillary-column gas chromatography/mass spectrometry at the U.S. Geological Survey California District Organic Chemistry Laboratory, 1996-99 /

Mode of access: Internet.

The complete cost-keeper; some original systems of shop cost-keeping or factory accounting, together with an exposition of the advantages of account keeping by means of cards instead of books.

Mode of access: Internet.